There is no repudiation of radical Islam in the Muslim world at large, so there most certainly will be a WW4 between Islam and the whole non-Islamic world.
There is next to no chance that Muslims will reform Islam in a civilized direction, so IMO “It’s On!”
“It’s on”, and may the best God win. Seriously. Some of them will defect to our side. Others will heed the call of jihad. We need to tell them that there will be no virgins, just death. Invite them to salvation. Not only salvation in the Biblical sense, but also in the personal sense. If they choose Islam, then so be it.